Khan.scratchpad.disable(); Kevin sells magazine subscriptions and earns $$8$ for every new subscriber he signs up. Kevin also earns a $$36$ weekly bonus regardless of how many magazine subscriptions he sells. If Kevin wants to earn at least $$72$ this week, what is the minimum number of subscriptions he needs to sell?
Explanation: To solve this, let's set up an expression to show how much money Kevin will make. Amount earned this week $=$ $ $ Subscriptions sold $\times$ Price per subscription $+$ Weekly bonus Since Kevin wants to make at least $$72$ this week, we can turn this into an inequality. Amount earned this week $\geq $72$ Subscriptions sold $\times$ Price per subscription $+$ Weekly bonus $\geq $72$ We are solving for the number of subscriptions sold, so let subscriptions sold be represented by the variable $x$ We can now plug in: $x \cdot $8 + $36 \geq $72$ $ x \cdot $8 \geq $72 - $36 $ $ x \cdot $8 \geq $36 $ $x \geq \dfrac{36}{8} \approx 4.50$ Since Kevin cannot sell parts of subscriptions, we round $4.50$ up to $5$ Kevin must sell at least 5 subscriptions this week.